kernel_optimize_test/include/net
Eric Dumazet 6f021c62d6 tcp: fix slow start after idle vs TSO/GSO
slow start after idle might reduce cwnd, but we perform this
after first packet was cooked and sent.

With TSO/GSO, it means that we might send a full TSO packet
even if cwnd should have been reduced to IW10.

Moving the SSAI check in skb_entail() makes sense, because
we slightly reduce number of times this check is done,
especially for large send() and TCP Small queue callbacks from
softirq context.

As Neal pointed out, we also need to perform the check
if/when receive window opens.

Tested:

Following packetdrill test demonstrates the problem
// Test of slow start after idle

`sysctl -q net.ipv4.tcp_slow_start_after_idle=1`

0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0    setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+0    bind(3, ..., ...) = 0
+0    listen(3, 1) = 0

+0    < S 0:0(0) win 65535 <mss 1000,sackOK,nop,nop,nop,wscale 7>
+0    > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 6>
+.100 < . 1:1(0) ack 1 win 511
+0    accept(3, ..., ...) = 4
+0    setsockopt(4, SOL_SOCKET, SO_SNDBUF, [200000], 4) = 0

+0    write(4, ..., 26000) = 26000
+0    > . 1:5001(5000) ack 1
+0    > . 5001:10001(5000) ack 1
+0    %{ assert tcpi_snd_cwnd == 10 }%

+.100 < . 1:1(0) ack 10001 win 511
+0    %{ assert tcpi_snd_cwnd == 20, tcpi_snd_cwnd }%
+0    > . 10001:20001(10000) ack 1
+0    > P. 20001:26001(6000) ack 1

+.100 < . 1:1(0) ack 26001 win 511
+0    %{ assert tcpi_snd_cwnd == 36, tcpi_snd_cwnd }%

+4 write(4, ..., 20000) = 20000
// If slow start after idle works properly, we should send 5 MSS here (cwnd/2)
+0    > . 26001:31001(5000) ack 1
+0    %{ assert tcpi_snd_cwnd == 10, tcpi_snd_cwnd }%
+0    > . 31001:36001(5000) ack 1

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-25 11:22:50 -07:00
..
9p 9p: switch p9_client_read() to passing struct iov_iter * 2015-04-11 22:28:27 -04:00
bluetooth Bluetooth: add hci_connect_le_scan 2015-08-10 21:36:13 +02:00
caif caif: fix a signedness bug in cfpkt_iterate() 2015-02-20 17:35:14 -05:00
irda irda: Convert function pointer arrays and uses to const 2014-12-10 15:33:16 -05:00
iucv af_iucv: fix recvmsg by replacing skb_pull() function 2013-04-08 17:16:57 -04:00
netfilter netfilter: nf_conntrack: add efficient mark to zone mapping 2015-08-18 01:24:05 +02:00
netns Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2015-08-04 23:57:45 -07:00
nfc nfc: netlink: Add capability to reply to vendor_cmd with data 2015-08-20 22:00:11 +02:00
phonet
sctp sctp: fix ASCONF list handling 2015-06-14 12:55:49 -07:00
tc_act net_sched: act_mirred: remove spinlock in fast path 2015-07-08 13:50:42 -07:00
6lowpan.h 6lowpan: add generic 6lowpan netdev private data 2015-08-11 22:05:36 +02:00
act_api.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-07-31 23:52:20 -07:00
addrconf.h ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument 2015-07-31 15:21:30 -07:00
af_ieee802154.h ieee802154: mac802154: remove FSF address 2014-10-25 08:07:30 +02:00
af_rxrpc.h af_rxrpc.h: Remove extern from function prototypes 2013-07-31 17:50:01 -07:00
af_unix.h net/unix: support SCM_SECURITY for stream sockets 2015-06-10 22:49:20 -07:00
af_vsock.h net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
ah.h ipsec: Remove obsolete MAX_AH_AUTH_LEN 2014-09-18 10:54:36 +02:00
arp.h neigh: Factor out ___neigh_lookup_noref 2015-03-04 00:23:23 -05:00
atmclip.h
ax25.h ax25: Stop using sock->sk_protinfo. 2015-06-28 16:55:44 -07:00
ax88796.h
bond_3ad.h bonding: Implement port churn-machine (AD standard 43.4.17). 2015-02-24 16:05:48 -05:00
bond_alb.h net: Move bonding headers under include/net 2014-11-10 13:27:49 -05:00
bond_options.h bonding: convert num_grat_arp to the new bonding option API 2015-07-27 01:05:24 -07:00
bonding.h bonding: Implement user key part of port_key in an AD system. 2015-05-11 10:59:32 -04:00
busy_poll.h sched, net: Fixup busy_loop_us_clock() 2014-01-13 17:39:11 +01:00
cfg80211-wext.h
cfg80211.h Merge branch 'mac80211' into mac80211-next 2015-07-17 15:39:41 +02:00
cfg802154.h ieee802154: add ack request default handling 2015-08-10 20:43:06 +02:00
checksum.h net: Add inet_proto_csum_replace_by_diff utility function 2015-08-17 21:33:06 -07:00
cipso_ipv4.h cipso: don't use IPCB() to locate the CIPSO IP option 2015-02-11 14:46:37 -05:00
cls_cgroup.h cls_cgroup: factor out classid retrieval 2015-07-20 12:41:30 -07:00
codel.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-05-13 14:31:43 -04:00
compat.h net: switch importing msghdr from userland to {compat_,}import_iovec() 2015-04-09 00:02:26 -04:00
datalink.h net: Move prototype declaration to header file include/net/datalink.h from net/ipx/af_ipx.c 2014-02-09 17:32:50 -08:00
dcbevent.h include/net/: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
dcbnl.h net/dcb: Add IEEE QCN attribute 2015-03-06 21:50:02 -05:00
dn_dev.h dn_dev: add support for IFA_FLAGS nl attribute 2013-12-10 21:50:00 -05:00
dn_fib.h decnet (dn*.h): Remove extern from function prototypes 2013-09-20 14:49:32 -04:00
dn_neigh.h netfilter: Pass socket pointer down through okfn(). 2015-04-07 15:25:55 -04:00
dn_nsp.h decnet (dn*.h): Remove extern from function prototypes 2013-09-20 14:49:32 -04:00
dn_route.h net: Move prototype declaration to appropriate header file from decnet/af_decnet.c 2014-02-09 17:32:49 -08:00
dn.h net: Move prototype declaration to header file include/net/dn.h from net/decnet/af_decnet.c 2014-02-09 17:32:49 -08:00
dsa.h net: dsa: Add dsa_is_dsa_port() helper 2015-08-18 14:17:21 -07:00
dsfield.h ipv6: Optimize ipv6_change_dsfield(). 2013-01-09 23:59:53 -08:00
dst_metadata.h route: move lwtunnel state to dst_entry 2015-08-20 15:42:36 -07:00
dst_ops.h net: Remove protocol from struct dst_ops 2015-03-09 16:06:10 -04:00
dst.h route: fix breakage after moving lwtunnel state 2015-08-23 16:51:17 -07:00
esp.h net: move pskb_put() to core code 2013-11-07 19:28:58 -05:00
ethoc.h net: ethoc: set up MII management bus clock 2014-02-04 20:19:51 -08:00
fib_rules.h fib: Add fib rule match on tunnel id 2015-07-21 10:39:06 -07:00
firewire.h firewire net, ipv4 arp: Extend hardware address and remove driver-level packet inspection. 2013-03-26 12:32:13 -04:00
flow_dissector.h mpls: Add MPLS entropy label in flow_keys 2015-06-04 15:44:31 -07:00
flow.h ipv6: route: extend flow representation with tunnel key 2015-08-20 15:42:37 -07:00
flowcache.h flowcache: Make flow cache name space aware 2014-02-12 07:02:11 +01:00
fou.h ip_tunnel: Ops registration for secondary encap (fou, gue) 2014-11-12 15:01:35 -05:00
garp.h garp.h: Remove extern from function prototypes 2013-09-20 14:49:33 -04:00
gen_stats.h net: sched: enable per cpu qstats 2014-09-30 01:02:26 -04:00
genetlink.h net: Introduce possible_net_t 2015-03-12 14:39:40 -04:00
geneve.h geneve: move definition of geneve_hdr() to geneve.h 2015-05-13 15:59:13 -04:00
gre.h gre: Remove support for sharing GRE protocol hook. 2015-08-10 14:03:54 -07:00
gro_cells.h ip_tunnel: Create percpu gro_cell 2015-01-18 01:56:32 -05:00
gue.h gue: Protocol constants for remote checksum offload 2014-11-05 16:30:03 -05:00
icmp.h icmp.h: Remove extern from function prototypes 2013-09-20 14:49:33 -04:00
ieee80211_radiotap.h mac80211: propagate STBC / LDPC flags to radiotap 2014-02-06 09:34:58 +01:00
ieee802154_netdev.h mac802154: cleanup llsec param flags 2015-06-12 11:42:29 +02:00
if_inet6.h ipv6: do retries on stable privacy addresses 2015-03-23 22:12:09 -04:00
inet_common.h net: Modify sk_alloc to not reference count the netns of kernel sockets. 2015-05-11 10:50:18 -04:00
inet_connection_sock.h tcp: fix child sockets to use system default congestion control if not set 2015-05-31 21:49:14 -07:00
inet_ecn.h tunnel: fix RFC number in comment for INET_ECN_decapsulate() 2014-05-07 15:30:52 -04:00
inet_frag.h inet: frags: remove INET_FRAG_EVICTED and use list_evictor for the test 2015-07-26 21:00:15 -07:00
inet_hashtables.h inet: simplify timewait refcounting 2015-07-09 15:12:20 -07:00
inet_sock.h inet: add IP_BIND_ADDRESS_NO_PORT to overcome bind(0) limitations 2015-06-06 23:57:12 -07:00
inet_timewait_sock.h inet: inet_twsk_deschedule factorization 2015-07-09 15:12:20 -07:00
inet6_connection_sock.h inet: get rid of central tcp/dccp listener timer 2015-03-20 12:40:25 -04:00
inet6_hashtables.h ipv6: get rid of __inet6_hash() 2015-03-18 22:00:35 -04:00
inetpeer.h tcp: simplify inetpeer_addr_base use 2015-03-31 13:58:35 -04:00
ip_fib.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-07-31 23:52:20 -07:00
ip_tunnels.h ip_tunnels: use tos and ttl fields also for IPv6 2015-08-20 15:42:36 -07:00
ip_vs.h net: Introduce possible_net_t 2015-03-12 14:39:40 -04:00
ip.h net: Set sk_txhash from a random number 2015-07-29 22:44:04 -07:00
ip6_checksum.h net: add gro_compute_pseudo functions 2014-08-24 18:09:23 -07:00
ip6_fib.h route: move lwtunnel state to dst_entry 2015-08-20 15:42:36 -07:00
ip6_route.h ipv6: Add rt6_get_cookie() function 2015-05-25 13:25:34 -04:00
ip6_tunnel.h udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb(). 2015-04-07 15:29:08 -04:00
ipcomp.h
ipconfig.h
ipv6.h ipv6: Enable auto flow labels by default 2015-07-31 17:07:12 -07:00
ipx.h switch ipxrtr_route_packet() from iovec to msghdr 2014-11-24 04:28:49 -05:00
iw_handler.h wext: add checked wrappers for adding events/points to streams 2015-02-28 21:31:12 +01:00
lapb.h lapb.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
lib80211.h lib80211: remove unused print_ssid() 2014-10-14 02:18:27 +02:00
llc_c_ac.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_c_ev.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_c_st.h llc: Make llc_conn_ev_qfyr_t function pointer arrays const 2014-12-10 15:21:24 -05:00
llc_conn.h net: Pass kern from net_proto_family.create to sk_alloc 2015-05-11 10:50:17 -04:00
llc_if.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_pdu.h net: llc: fix order of evaluation in llc_conn_ac_inc_vr_by_1 2014-01-01 22:22:43 -05:00
llc_s_ac.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_s_ev.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_s_st.h llc: Make llc_sap_action_t function pointer arrays const 2014-12-10 15:21:24 -05:00
llc_sap.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc.h llc: make lock static 2014-01-03 20:56:48 -05:00
lwtunnel.h lwt: Add cfg argument to build_state 2015-08-24 10:34:40 -07:00
mac80211.h mac80211: remove ieee80211_aes_cmac_calculate_k1_k2() 2015-08-13 11:31:45 +02:00
mac802154.h mac802154: do not export ieee802154_rx() 2015-07-23 17:10:50 +02:00
mip6.h include/net/: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
mld.h ipv6: mld: answer mldv2 queries with mldv1 reports in mldv1 fallback 2014-09-22 16:23:15 -04:00
mpls_iptunnel.h mpls: ip tunnel support 2015-07-21 10:39:05 -07:00
mpls.h openvswitch: Add basic MPLS support to kernel 2014-11-05 23:52:33 -08:00
mrp.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-10-01 17:06:14 -04:00
ndisc.h ipv6: ndisc: inherit metadata dst when creating ndisc requests 2015-08-20 15:42:37 -07:00
neighbour.h net: add explicit logging and stat for neighbour table overflow 2015-08-10 13:46:21 -07:00
net_namespace.h netfilter: nfacct: per network namespace support 2015-08-07 11:50:56 +02:00
net_ratelimit.h
netevent.h netevent/netlink.h: Remove extern from function prototypes 2013-09-21 14:01:39 -04:00
netlabel.h netlabel: fix the netlbl_catmap_setlong() dummy function 2014-08-07 20:55:21 -04:00
netlink.h netlink: implement nla_get_in_addr and nla_get_in6_addr 2015-03-31 13:58:35 -04:00
netprio_cgroup.h cgroup: clean up cgroup_subsys names and initialization 2014-02-08 10:36:58 -05:00
netrom.h netrom.h: Remove extern from function prototypes 2013-09-21 14:01:39 -04:00
nexthop.h
nl802154.h ieee802154: add ack request default handling 2015-08-10 20:43:06 +02:00
p8022.h p8022.h: Remove extern from function prototypes 2013-09-21 14:01:39 -04:00
ping.h net: Remove iocb argument from sendmsg and recvmsg 2015-03-02 13:06:31 -05:00
pkt_cls.h net: sched: remove tcf_proto from ematch calls 2014-10-06 18:02:32 -04:00
pkt_sched.h net: rename vlan_tx_* helpers since "tx" is misleading there 2015-01-13 17:51:08 -05:00
protocol.h net: Eliminate no_check from protosw 2014-05-23 16:28:53 -04:00
psnap.h psnap.h: Remove extern from function prototypes 2013-09-23 01:51:08 -04:00
raw.h raw/rawv6.h: Remove extern from function prototypes 2013-09-23 01:51:08 -04:00
rawv6.h raw/rawv6.h: Remove extern from function prototypes 2013-09-23 01:51:08 -04:00
red.h reciprocal_divide: update/correction of the algorithm 2014-01-21 23:17:20 -08:00
regulatory.h cfg80211: allow wiphy specific regdomain management 2014-12-17 11:49:55 +01:00
request_sock.h tcp: provide SYN headers for passive connections 2015-05-05 16:02:34 -04:00
rose.h rose.h: Remove extern from function prototypes 2013-09-23 01:51:08 -04:00
route.h route: move lwtunnel state to dst_entry 2015-08-20 15:42:36 -07:00
rtnetlink.h openvswitch: Use regular VXLAN net_device device 2015-07-21 10:39:07 -07:00
sch_generic.h net: sched: extend percpu stats helpers 2015-07-08 13:50:41 -07:00
scm.h scm.h: Remove extern from function prototypes 2013-09-23 01:51:09 -04:00
secure_seq.h inetpeer: get rid of ip_id_count 2014-06-02 11:00:41 -07:00
slhc_vj.h
snmp.h Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2014-10-15 07:48:18 +02:00
sock.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-07-31 23:52:20 -07:00
Space.h drivers: net: Include new header file in sbni.c 2013-12-19 18:51:20 -05:00
stp.h stp.h: Remove extern from function prototypes 2013-09-23 01:51:09 -04:00
switchdev.h net: switchdev: support static FDB addresses 2015-08-11 12:03:19 -07:00
tcp_memcontrol.h tcp_memcontrol: Kill struct tcp_memcontrol 2013-10-21 18:43:02 -04:00
tcp_states.h inet: add TCP_NEW_SYN_RECV state 2015-03-12 22:58:12 -04:00
tcp.h tcp: fix slow start after idle vs TSO/GSO 2015-08-25 11:22:50 -07:00
timewait_sock.h inet: remove BUG_ON() in twsk_destructor() 2015-07-09 15:12:20 -07:00
transp_v6.h ipv6: make IPV6_RECVPKTINFO work for ipv4 datagrams 2014-01-19 19:53:18 -08:00
tso.h net: Add a software TSO helper API 2014-05-22 14:57:15 -04:00
udp_tunnel.h udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb(). 2015-04-07 15:29:08 -04:00
udp.h net: Remove iocb argument from sendmsg and recvmsg 2015-03-02 13:06:31 -05:00
udplite.h net: switch memcpy_fromiovec()/memcpy_fromiovecend() users to copy_from_iter() 2015-02-04 01:34:15 -05:00
vrf.h vrf: vrf_master_ifindex_rcu is not always called with rcu read lock 2015-08-19 22:13:20 -07:00
vsock_addr.h VSOCK: Move af_vsock.h and vsock_addr.h to include/net 2013-07-27 22:14:06 -07:00
vxlan.h vxlan: GRO support at tunnel layer 2015-08-23 15:59:56 -07:00
wext.h wext.h: Remove extern from function prototypes 2013-09-23 16:29:40 -04:00
wimax.h net: treewide: Fix typo found in DocBook/networking.xml 2014-09-05 17:35:28 -07:00
x25.h x25.h: Remove extern from function prototypes 2013-09-23 16:29:41 -04:00
x25device.h
xfrm.h xfrm: Add oif to dst lookups 2015-08-11 12:41:35 +02:00